The big question in automotive marketing is how in-car systems, connected to the internet, will change the game. Photograph: Alamy

"Consumers are changing the way they choose their cars," says Chrissy Totty, head of innovation at BMW's media planning agency Vizeum. "We researched the consumer decision-making process and it is very different from even five years ago. It has become more complex and a lot shorter."

Traditionally a car purchase journey begins with a trigger, such as a new addition to the family or a promotion. Those triggers still exist, but customers today head online rather than to a dealer. "People used to go into dealerships a couple of times before making their choice. Now they are doing all their research online and they are going into the dealership with a clear picture of what they want. That is a challenge to agencies like us for how we can tap into that changed consumer decision making process."

Totty's comments are supported by research from consultants Arthur D Little, which reports that 70% of customers spend more time online than offline researching their car purchase. Online destinations include official vehicle web sites, online magazines and forums, and social media such as Facebook pages.

How then do you influence that online journey? The starting point is to get the web platform right, says Frank Wolfram, CTO of Geometry Global, which handles digital marketing for Volkswagen commercial vehicles. Most auto companies use one global integrated platform, which handles content management for web sites, integration with dealer systems, lease and finance calculators, and the all-important configurator that lets customers choose vehicle options online and see how it looks and what it costs. "Focus on your platform, focus on your core product which is to get informed people over to the dealers," Wolfram says.

These integrated global platforms are good for efficiency and consistency, but slow to adapt to changing needs because of their complexity. "In the Post-PC era, the tablet comes to the forefront," says Wolfram. Pumping up traffic to the site is little use if the destination site is not optimised for today's user, and adaptive to different types of user such as consumers versus business purchasers who are more interested in cost of ownership.

The decision-making process may be shortening, but marketers still need to think long-term because of the slow purchase cycle. "In the UK we renew our cars every 3 to 5 years. In Spain and Italy, people renew their cars every 8 to 10 years," says David Parkinson, General Manager of Social Media and Digital Engagement for Nissan. Consequently, Nissan focuses its social media marketing on brand reputation. "We see our job as affecting opinion. We closely track overall opinion versus brand share. We have a very good correlation between brand opinion and market share across Europe," he says.

Nissan runs social media campaigns, like Nissan Juke Ride which crowd-sourced the design of a custom vehicle using key online influencers, then built it and showcased the results; or the forthcoming Nissan Note campaign in which bloggers get vehicles on loan and share their best moments online.

A key future objective though is increased active participation in online communities. "Peer reviews are becoming more and more important. One of my big focuses is to start getting in and engaging with the communities and early adopters online. Where things are incorrect on a forum or blog, it is our job to go out and say, here is our point of view. That is how we improve our brand recognition."

Nissan uses social media listening tools to find and analyse online conversations. "The main tool we use at the moment is called Synthesio," he says, which is similar to other tools like Radian 6 and Brandwatch that are popular in the UK. Social reputation score is our key metric," he says.

The big question in automotive marketing is how in-car systems, connected to the internet, will change the game. "The actual car; the engine, the wheels, the drive shaft, the bodies, those have become commodities. The differentiator for cars is the in-dash system, the computer," says Patrick Salyer, CEO of Gigya, which works on social media engagement for brands including Honda, Hyundai and Toyota. "The ability for a car to deeply know who you are and be able to make recommendations and personalisations because of that will become very interesting. This is based on the concept of social login, where you can login to your Facebook, Twitter and LinkedIn, and in this case you are also logging into your car." For example the car might tell you that your Facebook friend is at a nearby coffee shop, or that a deal is available at a local restaurant.

Nissan is integrating wearable technology with its in-car system using a connected smart watch called Nismo. "Nismo can be connected to your car experience and also your heart rate and so on, and then you can share those stats socially in the same way that you do with a Nike+ FuelBand," says Parkinson. "The new Nissan Qashquai has Facebook notifications which comes through to your car, Twitter notifications, and Trip Advisor built in," though he adds that distracting notifications only arrive when you are not driving.

The advent of connected cars has two implications. One is that it makes the automobile part of a driver's social media world, increasing interaction. More profoundly, it has the potential to allow auto companies to know their customers as never before.

"If car companies can connect with their customers' social login, they can build a permanent lasting relationship," says Salyer. "If the car company tracks things about me like my driving habits and where I go, it is actually a value add insight. That is a reason to stay with that car company."

Salyer expects a battle between auto companies and internet giants like Google and Facebook to own that data. "There is going to be an all-out war for who owns that connected car experience. I don't think the car companies want to give that up and I think the likes of Google are very interested in owning it."

Few people buy cars online, and that is not expected to change. Just 6% of car sales will be online by 2020, predicts Arthur D Little's report. Do not be fooled though; increasingly the decisions are taken online with the final test drive simply sealing the deal.